Advent Botany 2015 – Day 19: Popcorn tree decorations

By now most of us will be adorning our Christmas tree with dazzling decorations and scrummy treats. This year I have a new eye catching addition, strings of popcorn. I’d not heard of this American tradition until this year but the fluffy cream trails of popcorn have been draped over fir branches for over a century across the water.

During the First World War Alice Bradbury a cooking journalist asserted that popping corn was a patriotic occasion. There are rather wonderful tales of the thanksgiving peace negotiations where Indians are said to have brought along deer skin bags of popcorn to meet with Pilgrims. However, it is more likely that the popularity of popcorn with children led to associations with occasions, especially with the festival of Christmas.

Popcorn garlands were firstly created by colonists who adapted the European tree decorating traditions. With a big needle popcorn is strung creating lines which can be wrapped around the tree. Popcorn sculptures were also popular with mini Christmas trees created with popcorn which were skewered to an apple base. These creations store well and so alike other Christmas decorations, popcorn garlands have become family heirlooms.

A Christmas tree draped with a popcorn garland and hand blown glass ornaments from Germany (Photograph copyright West Virginia and Regional History Center, West Virginia University, reproduced with permission)

The oldest ears of popcorn ever found were discovered in the Bat Cave of west central New Mexico in 1948 and 1950. The true age of the popcorn is in dispute but they are thought to be thousands of years in age. Christopher Columbus and his crew were the first westerners to see popcorn as natives of the West Indies exchanged goods for popcorn headdresses. In 1612 French explorers documented the popping of corn using hot sand by the Iroquois who consumed the popcorn in soup and beer.

Not giant popcorn, but small xmas trees.

Of course, popcorn is made from the kernels of Maize Zea mays subsp. everta part of a species complex which is well known as a commercial crop for food production. At the plant apex there is a single male inflorescence tassel and between some of the leaf sheaths and the stem there are the stigma ‘silks’ of the female inflorescences. Once pollination has occurred the carpels at the end of the silks develop into rows of kernels sat on a white pithy centre. Upon heating the kernel the moisture inside causes the flesh to expand and burst the pericarp producing mushroom or snowflake shaped flakes. Ears produce a mixture of each popcorn shape variant but the snowflake is more desirable for consumption as it is softer on the palate.

Zea mays plant (CC0)

A solution to this issue was discovered when hybrids were developed to eliminate the mushroom producing kernels. In 1934 the Minnesota Agricultural Experiment Station released the first popcorn hybrid for commercial use called Minhybrid 250. By the 1940s hybrids had completely surpassed the open-pollinated varieties for popcorn production. Popcorn kernels are harder with the thickest pericarp and a much greater hard endosperm to soft endosperm ratio. In comparison to dent corn the popcorn plant has a larger tassel, thinner leaves and weaker stems and so is more prone to buckling. New hybrids have continued to be developed to strike a balance between agronomy limitations and the the quality and quantity of kernel production. This continued investment shows that popcorn is an established part of American culture.

Why don’t you try it for yourself? Nowadays popcorn garlands are often stained with food colouring and so you can have a rainbow string of popcorn if you wish!